This disclosure relates in general to surgical devices and procedures, and more particularly, to internal fixation devices, the associated instrumentation and procedures for the repair of fractured bones.
Hip fracture nail (HFN) systems (also referred to as reconstruction nail systems) are currently available for surgically treating a wide range of proximal femoral fracture indications. HFN systems include an intramedullary nail that is sized and shaped for surgical implantation into the intramedullary canal of the fractured, proximal femur. The proximal portion of the nail has a smooth, transverse bore that retains a lag screw or the like having a distal end that anchors into the femoral head of the femur, such that the construct holds the femoral neck and the diaphysis (shaft) of the femur at a fixed angle with respect to each other, while allowing “sliding compression” of the fractured, proximal femur to promote proper healing. Typically this neck/shaft angle is in the range of 125 to 130 degrees. The proximal portion of the nail may also include another transverse, smooth bore that retains an anti-rotation screw alongside and proximal to the lag screw. Manufacturers typically provide HFN systems with both long and short versions of the nail and in various sizes to accommodate patient anatomy variations.
Surgeons usually implant the hip fracture nail and screws with the aid of an x-ray radioscope (fluoroscope) in order to verify proper reduction of the fracture and to properly position the nail and screws in the femur. It is especially important to insert the distal end of the lag and antirotation screws into the central portion of the femoral neck and head so as not to weaken the construct or to break out through the articulation surface of the femoral head. Therefore, manufacturers have provided special instrumentation for implanting the HFN system. Such instrumentation typically includes a target jig that attaches to the proximal end of the nail. The target jig provides a handle for holding and positioning the nail into the femur with the aid of radioscopic visualization. The target jig also includes target holes aligned with the lag screw and antirotation screw holes in the nail, to aid the surgeon in drilling the pilot holes into the femoral neck and head to receive the lag and anti-rotation screws. Portions of the target jig may be radiolucent in order to radioscopically visualize the nail, while other portions of the target jig may be radio opaque in order to provide visual references for aligning and positioning the nail inside the femur so that the axis of the lag screw passes approximately through the center of the femoral neck and head. Unfortunately during current standard HFN implantation procedures, it is usually necessary for the surgeon to take several radioscopic images in the lateral-medial and anterior-posterior directions in order to reduce the fracture and to properly position the nail in the femur. This is primarily because it is often difficult for the surgeon to discern if the radioscopic view is optimal for directing a guide wire through the femoral neck and to the proper depth in the femoral head. The guide wire is needed for guiding a cannulated drill to create a pilot hole for the lag screw. Clearly, each radioscopic image increases exposure of the surgeon, staff and patient to radiation and adds to the surgical procedure time and costs. What is needed, therefore, is improved instrumentation to aid the surgeon in properly implanting a hip fracture nail into the femur of a patient when the instrumentation is used in conjunction with a radioscopic imaging device.
Another challenge faced by orthopaedic surgeons is effectively managing a number of differently configured and sized IM nails and instruments that are provided by manufacturers due to the variation of patient anatomies. Currently available HFN systems include sets of IM nails in various sizes for each of a plurality of femoral neck/shaft angles. Each of these neck/shaft angle sets require a dedicated target jig, so it is necessary to match the correct IM nail with the correct target jig when attaching the IM nail to the target jig during the surgical procedure. Obviously, mismatching the IM nail and target jig may extend the duration of the procedure and cause unnecessary contamination of sterile components, resulting in higher surgical costs. What is also needed, therefore, is an improved HFN system to reduce confusion during the surgical procedure related to matching each of the angular versions of the IM nail to its dedicated target jig.